How to test glow plugs???

[slojoexxx]

I would like to know how to test a Glow Plug???

Thanks Doc.

[mobetta]

ut of car- hook to 12v- if it gets hot, it's good.

in car- I often just take a test lite and run it from 12v+ to the tip of the GP where the wire goes, or tothe harness on the relay end after unplugging it from relay. if it lites up, prolly good unless there is a direct ground(never happened yet)

this has been covered a few hundred times- search it up.

[slojoexxx]

I did look it up, but no one said how to really do it,do you use jumper cables???

I have pulled one out and testing it, as I know that either one or two are bad...

Thanks Doc.

[Knightrider966]

Originally Posted by slojoexxx

I would like to know how to test a Glow Plug???

Thanks Doc.

The best way is to remove it and connect it to the hot terminal of the battery while grounding it up against the engine block or some easy place suitable, but preferrably not to the negative terminal of the battery. If the tip glows red, it's a good one and if not, replace it.

Best way to measure performance I'm aware of.

[engatwork]

Get a couple of pieces of wire, preferably with alligator clips on the ends. Touch one end to the + terminal of the battery and have it on the threaded end of the gp. Use the other wire to touch the body of the gp to the negative terminal of the battery. Don't be holding the gp when you do it.

[oldiesel]

Much easier to do the test light test while they are still in the car.Some are not easy to get out so unless you are planning on replacing all test them in the car so you dont have to take out the ones that are good.My $.02 Don

Originally Posted by engatwork

Get a couple of pieces of wire, preferably with alligator clips on the ends. Touch one end to the + terminal of the battery and have it on the threaded end of the gp. Use the other wire to touch the body of the gp to the negative terminal of the battery. Don't be holding the gp when you do it.

I just use jumper cables, grab the body of the GP with the negative cable clamp and touch the positive clamp to the contact.

[Jimmy Joe]

you should google Dieselgiant's write-up on testing glow plugs; there is no way I would go through the effort and rip my hands up taking the plugs out unless i had reason to suspect them.
Then i would just go ahead and change them,

Do Not Use Autolite or other garbage from you local parts store, even if it is cheap, unless you want to do it all over again in a few months!!! don't ask me how i know...

Phil has em for 10 bucks a piece for nice German ones, that is the way to go!

I agree, I only test the resistance unless I have reason to suspect a problem. But if you do want to test one out of the car, the jumper cable method seems to be the easiest/safest.

[mobetta]

I use a jump box out of the car.

FWIW- 4/5 bosch(french!!?) plugs did not last me a year.

I now buy what I can local, and use antiseize.

[slojoexxx]

Thanks guys for all your tips, my jumper cables are junk so that didn't work and my jumper wires that I had didn't to work either. So I used lead #1 and a pair of small vise grips and wegged it next to the valve cover and then just turned the key on. Bam an instant answer. 3 out of 5 bad...

That is a pure pleasure to do... BAHAHAHA

But she starts up like right now... Wish I do this months ago...

Doc.

[Deni]

I use a multimeter. Without even removing the gp I can see if it's good or not. A good gp should give about 1.4-1.6 ohms. A bad gp that is ~15 ohms will still get hot, but not that fast and not so hot.